The United States is home to 59 officially designated National Parks, the approximate locations of which appear on the map below. Using the mathematical concept of Voronoi tesselation, reddit user wouj divided the map into sections that can help you determine which national park is closest, geographically, to your particular point of origin. In a nutshell, each "Voronoi region" contains a national park, along with every geographical point whose distance to that park is less than or equal to its distance to any other national park. Click the image below to enlarge.
"I think Voronoi diagrams are already a pretty beautiful and interesting mathematical structure," wouj tells io9, "but beyond that, the question of which national park is closest to a given area seemed worth asking." People typically drive or roadtrip to national parks, wouj reasons, and a Voronoi diagram is a nice way to visualize the consideration of distance one might make when selecting a destination.
The map is not perfect. Proximity as the crow flies is not necessarily as relevant to roadtrippers as, say, the quickest driving times. Similarly, national parks are not point locations; that these parks are spread out means there's a good chance their outer reaches are at times more accessible than the map would suggest. A few other inaccuracies and limitations have been enumerated in the thread where this map first appeared, but as wouj telss us, the map was never meant to be "a super serious project":
I have an amateur interest in math and a little work experience in GIS (I spent a summer making maps for a website, basically), but I didn't use GIS for this map (although it would look much nicer if I had!) I just used this online tool (http://lpetrich.org/Science/Geomet…) to make the Voronoi diagram, put some labels on it in Inkscape, and here we are.
Serious project or no, it's a clever little overlap of geography and mathematics, and one that lends itself to some rather curious observations (Dry Tortugas National Park, for instance, despite being located in Florida, manages to be the closest national park to exactly nowhere in the continental U.S.). Check out the original thread over on reddit for more insight and information.